Best way to validate Pojo

Question

I have the below Pojo which I need to validate. All the below fields are mandatory but they can have null values.I can use @JsonCreator to make fields required but sonar rules complaining since i have many fields.Is there any other elegant way to solve this problem? I am using Spring Boot ,Jackson and Java 8. @Valid public class Bar {

    @Length(min = 1, max = 2)
     private String bid;
    
    @JsonProperty(value="bname")
    private String bname;
     //i have 10 more fields omitted for brevity

This should be the only valid json

"bar":{"bid":"1","bname":"w"}

But currently i am able to process this invalid Json too which is incorrect

"bar":{"bid":"1"}